The present invention relates to an electric lock system and, particularly, to an electric lock system in which the locking operation is controlled and monitored by an electric signal.
In the past, in order to control an electric lock device, a detector which operates upon conditions such as the opening and closing of a door and locking and unlocking of the lock device is provided for each lock device. The detector is usually connected to a control panel installed remotely therefrom through a plurality of lead wires and, in addition, a plurality of lead wires are required to supply electric power for driving a solenoid of the electric lock device. Therefore, the total number of lead wires required for each lock device is relatively large.
For example, an electric lock system disclosed in Japanese utility model publication No. 6877/1966 requires three lead wires between a lock device and an indicator. Another electric lock system, disclosed in Japanese Patent Publication Nos. 21184/1967 and 21186/1967, also requires three lead wires. Further, a lock system disclosed in Japanese Utility Model Disclosure No. 12294/1973 requires five lead wires between the lock device and control panel.
In a situation where such a control panel or control device is required, it is usual that a large number of lock devices are monitored and controlled thereby. Therefore, the total number of lead wires becomes very large resulting in many economical and technical disadvantages. If the number of lead wires for each lock device can be reduced, the disadvantages will be eliminated or remarkably improved.